We studied 14 chronic toluene abusers with a comprehensive neuropsychological evaluation and cerebral magnetic resonance imaging (MRI). There were 10 men and 4 women, and the mean age was 29 years. Using a blinded global assessment of neuropsychological functioning, we found 3 patients to be normal, 3 in a borderline range, and 8 impaired. Independent analyses of white matter changes on MRI disclosed that the degree of white matter abnormality was strongly correlated (p < 0.01) with neuropsychological impairment. Dementia in toluene abuse appears to be related to severity of cerebral white matter involvement.